Toby wrote:but it runs on a car battery only...no newer model with a battery included?

They definitely have new models with included battery. In fact I think they've gone to NiMH or even lithium batteries. Personally, I'd buy a 12V gel cell for $20 and save a few bucks (that will work exactly like a car battery).

You can buy the analog version with regular manometer or the digital version. Then, you have the choice of buying just the pump with no battery or charger OR the pump with the gel type battery (small 12V 7A/hr) OR the one with the Nimh battery. Personnaly I think I will go with the pump only, digital version and I will use a Lipo pack that I have here for RC airplane. This way, I''ll save $100! I am now looking for a Canadian dealer to save on duty, if anyone know where I could buy it in Canada, let me know.

The lead gel cell battery is about 3 times as heavy, and cannot be recharged as many times... but I would get the lead battery, still, for the sake of simplicity, recycling, and other reasons.

If weight really matters a lot to you, then you could buy a Lithium Ion battery pack... but you would be in for more complexity and expense. Probably, the only kiters who would consider using the Lithium Ion battery are those who already are familiar with the use of such batteries, through the use of some other hobby, like radio-controled devices (airplanes, boats, etc).

For the average "Joe Kiter", who does not know a lot about electronics, does not even own a multimeter, doesn't know what 'polarity', amp hours, or reverse polarity, means, and does not want to know about techy stuff, the sealed lead battery (gel) would be the best choice.

The lead gel cell battery is about 3 times as heavy, and cannot be recharged as many times... but I would get the lead battery, still, for the sake of simplicity, recycling, and other reasons.

How you treat the batteries is critical. In a real-world scenario I'd say the gel-cells will usually take a lot more cycles than a NiMH. This is only because the NiMH is much more sensitive to being treated badly. But unlike NiCAD's, none of the mentioned batteries will respond well at all to a deep discharge. They can all be ruined quickly that way.

I use all three types for all sorts of things. But for this application the gel-cell is still the ticket. The gel-cell in my pump is several years old and has several hundred cycles on it.

No matter which battery you choose, it's critical that you get the right type of charger for that type of battery. They have different charge cycles, and leaving any of them on charge on the wrong kind of charger will ruin them. The lithiums are famous for their tendency to explode.

If you want a bullet-proof arrangement, you can get a battery and charger intended for a quality cordless drill. They have their own internal protection circuitry that will prevent them from over-charging, over-discharging, etc.

That being said, I'd personally keep it simple. This arrangement will be cheap and safe: